Issue 36, 5 October 2008 -- 39th Apollo Anniversary Year

  1. News: The Space X / Falcon 1 success on 28 September
  2. Elon Musk at the Royal Aeronautical Society -- report by Stephen Ashworth
  3. Beyond Mars, by Stephen Ashworth
  4. Resource wars and Gerard O'Neill's space colonies -- letter from Jerry Stone

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(1) News: The Space X / Falcon 1 success on 28 September

Jeff Foust on the successful Falcon 1 launch:

"While China's Shenzhou 7 mission last week will got more attention, it may be the SpaceX launch that is more influential in the long run." -- "China is following the same path forged nearly five decades ago by the United States and the former Soviet Union: a government-run human spaceflight program that is as much for national prestige as for anything else. [...] SpaceX, and other NewSpace ventures like it, carry the promise of dramatically changing the space industry with low-cost orbital and suborbital launch options that open up new and potentially lucrative new markets. That promise, though, has remained just that -- a promise, not a reality -- since SpaceShipOne won the Ansari X Prize four years ago. Sunday's launch was perhaps the biggest milestone since then in demonstrating what NewSpace can offer."

Read the full article in The Space Review.

Also Charles A. Lurio in The Lurio Report (News and Analysis of the "New Space" Enterprise):

"This is a tremendously important day in the history of spaceflight, not just of one company. It should start to silence the critics from the Old Space camp: you can -- indeed, perhaps must -- start from scratch, cut the costs of components and vehicles and succeed."

"Only the choice of the New Space framework can produce the change that the nation needs for spaceflight, change which could make it explode as an engine of prosperity comparable to the PC/IT revolution and of practical space science and exploration. Today's Falcon flight can be a bright glint of the new dawn for the Space Age that's just over the horizon."

(Thanks to Dean Filipovich for passing this on to me.)

-- S.A.

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(2) Elon Musk at the Royal Aeronautical Society

Report by Stephen Ashworth

What is needed to extend life permanently beyond Earth?

On 3 July 2008, US astropreneur Elon Musk gave a short lecture and answered questions on this theme at the Royal Aeronautical Society's headquarters in London. Musk is the owner and CEO of Space X, a company which is aiming to replace the Space Shuttle as America's principal means of access to the International Space Station with its Falcon rockets and Dragon capsule.

Musk takes a long view of human evolution: what stands out in the history of life, he said, is that life becoming interplanetary in scope is if anything even more significant than its emergence from the oceans to colonise the land, some 400 million years ago. This new development transcends our parochial human struggles, and it is incumbent upon us to act to secure the colonisation of space while it is still possible.

According to Musk, O'Neill colonies are not the way to go, and neither is the Moon a good option. You cannot grow a space station without grabbing mass from somewhere; meanwhile, the Moon is resource-poor.

We need a planet, and the only good option for us is Mars.

But to get to Mars, we need reusable transport. Any transport system whose elements are used once only sees very little overall use, because of its high cost per journey. Consider an airliner: it may take you from London to Los Angeles for 500 dollars -- yet the aircraft itself cost many millions of dollars to build. We need a similar reusable system for getting to Mars, as we will need to transport tens of thousands of tonnes to the planet in order to set up a self-sustaining ecology there.

Space X is developing the Falcon 9 rocket, whose first and second stages parachute back to Earth for re-use, to carry the Dragon capsule, whose propellants and consumables tanks are enclosed within the main aeroshell in order to reuse it as fully as possible. Dragon is designed to carry out completely autonomous cargo supply missions, or to carry a crew of up to seven astronauts.

The first launch of the Falcon 9 rocket, capable of carrying 10 tonnes to orbit, is expected in the second quarter of 2009. A Falcon 9 heavy, with a payload of up to 30 tonnes, is also in development -- this appears to be effectively three Falcon 9s in parallel. Operational missions to the ISS are planned by the end of 2010, as well as the launch of the Sundancer space station module for Bigelow Aerospace.

The rocket stages depend on parachutes to return to Earth because the development cost of this type of system is much lower. But, looking further down the road, winged rocket stages for an aeroplane-style landing are clearly superior.

He does not believe that single-stage to orbit is practical -- trying to do SSTO and at the same time make it reusable is "a bridge too far". (Whether he is acquainted with the details of Britain's Skylon project for a reusable SSTO spaceplane was not clear.)

I asked Musk how he saw his business growing in terms of its various potential markets -- government space science, space tourism and space-based solar power systems.

He said that he is a major investor in terrestrial solar power systems, so one would have thought that he would support solar from space, but in fact he does not. In Musk's view, the economics of space-based solar power do not make sense. When another questioner challenged him on the recent NSSO report, he went so far as to say: "It's a question of comparative economic viability. Even if you could teleport hardware to space for free, space-based solar power would still not make economic sense."

He sees the goal to aim at as being to bring down the cost of going to Mars until it is similar to the cost of buying a house -- say, 2 million dollars for a one-way trip to Mars. This is "the only economic model I can think of" which will succeed in extending life permanently beyond Earth.

See recent commentary by Jeff Foust on SpaceX, Falcon and Elon Musk's future plans.

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(3) Beyond Mars

by Stephen Ashworth

According to Elon Musk, we can only colonise a resource-rich planet. This is a little unfortunate, as the only extraterrestrial candidate in our Solar System is Mars.

The Musk economic model is similar to the one proposed by Robert Zubrin in chapter 8 of his well-known book The Case for Mars. By assuming the use of reusable methane/oxygen SSTO spaceplanes to get from the surface of Earth into low Earth orbit and Earth-Mars cycler stations for the interplanetary voyage, Zubrin arrives at about a third of a million dollars for the one-way ticket price to Mars -- roughly the cost of a decent house in suburban America, or equivalent to the life-savings of a middle-class family. (Since he was writing over ten years ago, this is probably by now very similar to the 2 million dollars given by Musk in his talk.)

Zubrin too argues that the Moon is of relatively little interest, because it is resource-poor, and he argues that human activity in the asteroid belt will remain dependent upon supply from Mars.

But there is a contrasting model which offers a broader vision for the future.

Firstly, on a planet like Earth or Mars, almost all the mass of the planet has only one function: to provide surface gravity, and all the things that one gets along with gravity such as an atmosphere and geological activity. This is a low-tech use of mass, and it is highly inefficient.

How massive would a space colony in the form of a rotating O'Neill cylinder need to be? We don't know, because nobody has ever tried to build one. But if we assume that its length is several times its radius, and that its hull requires several tonnes per square metre for the outer pressure vessel, radiation shield (probably a layer of water), stiffening frames and internal flooring and superstructure, then we are looking at several million tonnes per square kilometre of habitable area with gravity.

(The classical design uses only half the floor area for habitation and the other half for windows, but given the economic pressure to accommodate as many people as possible I predict that O'Neill colonies will use almost all their floor area for habitation and bring sunlight in through fibre-optic cables along the axis, along with extensive internal electric lighting.)

So for example: length = 5 times radius and area density of hull = 10 tonnes/sq metre gives us total mass of 12 million tonnes/sq km. By contrast, Earth, Mars and the Moon have masses of several trillion tonnes per sq km of surface area.

Compared with a planet, an O'Neill cylinder would then be somewhere between 100,000 and one million times more efficient at using mass to create surface area with gravity. It would also be vastly more economic to get from one O'Neill cylinder to another than from one planet to another, since the gravitational well at the inside surface of a cylinder is trivially small, and can be overcome by simply walking up a few hundred metres of staircase.

Against this, Elon Musk asserts that you cannot grow a space station without "grabbing mass from somewhere". So let's do exactly that.

The main asteroid belt offers in total about three times the mass of its largest member, Ceres, thus amounting to about a twentieth of a lunar mass, 3 million trillion tonnes, of raw materials which are already in space. If this could all be used to manufacture O'Neill cylinders (remembering that main-belt asteroids contain a useful mixture of rocky, icy and metallic substances) then it would give us a total habitable area of half a trillion sq km -- one thousand times the surface area of planet Earth itself, and several thousand times that of Mars.

This emphasis on space construction nicely dovetails with present-day development of the technologies needed for space-based solar power, as well as providing that power source with a constantly expanding market. Future human populations could run into the trillions.

Yes, we will go to Mars, and we will colonise it. But in order to reach Mars, we will in any case need to build prototype space colonies in cycler orbits. Thus the effort to colonise Mars will lead naturally on to O'Neill-type colonies.

The main theme of the next millennium will be the evolution of the human species from a planet-bound one to a space-based one. The Zubrin-Musk paradigm of Mars colonisation will be a small part of the unfolding picture. It will be a stepping-stone to greater things.

Over against the currently fashionable political pessimism about the human future, we must assert that we are on the verge of thousands of years of renewed dynamic growth and wealth creation.

Our space agencies should be leading the way, not dreaming of flying re-runs of Apollo!

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(4) Resource wars and Gerard O'Neill's space colonies

Letter from Jerry Stone

The question about the fear of resource wars reminds me of comments by the sadly missed Gerard O'Neill.

In the closing pages of his book, "The High Frontier", he lists the benefits of developing space colonies and space-based manufacturing. Apart from the direct benefits that such activities offer, he included the following as a bonus to humanity offered by the programme:

"Reducing the incidence of wars and the constant threat of wars, by opening a new frontier with virtually unlimited new lands and new wealth."

Certainly if countries do not have to compete with other for resources, no-one can deny the great benefit that would bring.

I quote these benefits in my presentation "Colonies in Space", which also includes information on the colonies being used to construct solar power satellites to provide energy for Earth. The plans drawn up in the 1970s, based on materials and technology available at the time, showed that solar power satellites, along with other exports from the colonies to Earth, could result in the entire programme -- including construction of the colonies themselves -- paying for itself in 27 years. Bearing in mind the huge construction cost and the expectation that electricity from the SPS array would be sold at only 1 cent per kW-hour (about 1/20 of today's prices) one can begin to realise the extent of the provision to Earth.

For comparison, according to NASA, each shuttle launch costs $450 million, and the shuttle has now been flying for 27.5 years. I am sure that NASA would love to have recovered the total cost of the programme by now!

However, as I also mention in my presentation, the development of launch systems by private enterprise, combined with the renewed interest in SPS systems (as described by Coyote Smith at the BIS), leads to renewed hope that the development of the colonies may yet be realised.

Anyone who would like to book my presentation is welcome to contact me for details.


Jerry Stone FBIS FRAS
Freelance Presenter on Astronomy and Space Exploration

Chairman, The Space Education Council

STEMNET Science & Engineering Ambassador

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